1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ECB: Electronic CodeBook mode 4 * 5 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> 6 */ 7 8 #include <crypto/algapi.h> 9 #include <crypto/internal/cipher.h> 10 #include <crypto/internal/skcipher.h> 11 #include <linux/err.h> 12 #include <linux/init.h> 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 16 static int crypto_ecb_crypt(struct skcipher_request *req, 17 struct crypto_cipher *cipher, 18 void (*fn)(struct crypto_tfm *, u8 *, const u8 *)) 19 { 20 const unsigned int bsize = crypto_cipher_blocksize(cipher); 21 struct skcipher_walk walk; 22 unsigned int nbytes; 23 int err; 24 25 err = skcipher_walk_virt(&walk, req, false); 26 27 while ((nbytes = walk.nbytes) != 0) { 28 const u8 *src = walk.src.virt.addr; 29 u8 *dst = walk.dst.virt.addr; 30 31 do { 32 fn(crypto_cipher_tfm(cipher), dst, src); 33 34 src += bsize; 35 dst += bsize; 36 } while ((nbytes -= bsize) >= bsize); 37 38 err = skcipher_walk_done(&walk, nbytes); 39 } 40 41 return err; 42 } 43 44 static int crypto_ecb_encrypt(struct skcipher_request *req) 45 { 46 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 47 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm); 48 49 return crypto_ecb_crypt(req, cipher, 50 crypto_cipher_alg(cipher)->cia_encrypt); 51 } 52 53 static int crypto_ecb_decrypt(struct skcipher_request *req) 54 { 55 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 56 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm); 57 58 return crypto_ecb_crypt(req, cipher, 59 crypto_cipher_alg(cipher)->cia_decrypt); 60 } 61 62 static int crypto_ecb_create(struct crypto_template *tmpl, struct rtattr **tb) 63 { 64 struct skcipher_instance *inst; 65 int err; 66 67 inst = skcipher_alloc_instance_simple(tmpl, tb); 68 if (IS_ERR(inst)) 69 return PTR_ERR(inst); 70 71 inst->alg.ivsize = 0; /* ECB mode doesn't take an IV */ 72 73 inst->alg.encrypt = crypto_ecb_encrypt; 74 inst->alg.decrypt = crypto_ecb_decrypt; 75 76 err = skcipher_register_instance(tmpl, inst); 77 if (err) 78 inst->free(inst); 79 80 return err; 81 } 82 83 static struct crypto_template crypto_ecb_tmpl = { 84 .name = "ecb", 85 .create = crypto_ecb_create, 86 .module = THIS_MODULE, 87 }; 88 89 static int __init crypto_ecb_module_init(void) 90 { 91 return crypto_register_template(&crypto_ecb_tmpl); 92 } 93 94 static void __exit crypto_ecb_module_exit(void) 95 { 96 crypto_unregister_template(&crypto_ecb_tmpl); 97 } 98 99 subsys_initcall(crypto_ecb_module_init); 100 module_exit(crypto_ecb_module_exit); 101 102 MODULE_LICENSE("GPL"); 103 MODULE_DESCRIPTION("ECB block cipher mode of operation"); 104 MODULE_ALIAS_CRYPTO("ecb"); 105